The InMoDam IPN project aims at developing a practical toolbox of sensors and instruments, including digital processes and adapted methods that will measure loads and damages that might result from wind, waves and ice attacking the upstream slope of embankment dams. The objective is to gain new knowledge related to the size of the loads and the potential damages to project future performance of the dam and thereby improve dam safety. Included in scope is also the design of erosion protection of the upstream slope.
The project idea is to utilize technologies already developed in f.ex. the offshore industry and marine constructions and placed in rough climates and adapt to the hydro reservoirs in mountainous Nordic regions. The development of such type of technologies has been immense the latest years, but the dam industry has yet to utilize these techniques to the full extent.
The project will install sensors and instruments at a minimum of 3 Norwegian dams both for measuring the size of the attacking loads and will also measure changes and damages to the constructions.
The Norwegian hydro industry represented by Agder Energi, Hydro, Sira-Kvina, Trønder Energi, BKK, Hafslund Eco, Sunnhordland KS and Statkraft are financing the approximately half of the project and the NRC supports with the remaining budget. The research team consist of specialist from leading scientific communities in Norway as NTNU and HydoCen, Multiconsult, Norconsult and Energy Norway. The regulatory authorities NVE will also be a formal partner in project and contribute with perspective and knowledge into the project analyses and discussions.
The research project will provide dam owners and their service providers (consultancies and technology suppliers) a practical toolbox of applicable methodologies and technologies for monitoring loads, upstream face, and the potential implication of changes to dam safety. From the regulatory perspective, the toolbox can be used to verify actual loads and future projections of dam safety performance.
The project includes installation of wave and wind monitors on at least three different reservoirs for the development of methodologies to predict actual loads more accurately. A number of candidate reservoirs and dams have already been identified. The wave measurements will be used to calibrate numerical models as those widely used for wave prediction in coastal engineering. The measurements will also be used in assessments of riprap condition and its relation to loading history.
These parameters will complement methodologies for characterization of dam condition, failure mechanisms and detection of change, both sub-aerially (e.g drone photogrammetry or LIDAR scan) and underwater through use of technologies such as multi-beam sonar. Since upstream dam faces in Norway are often covered in snow and ice when they are not underwater, there is a particular need for more accurate surveying underwater.
Such technologies are available and used in the offshore industry (for example multi-beam sonar from ROV), but have not been applied in mountain reservoirs with the challenges that entails in relation to access. The project will develop methodologies to transfer and adapt appropriate technology from the offshore and coastal engineering industries. Instrumentation to give real-time information on change would allow for faster reaction times and a higher degree of confidence in the dam’s condition. Methodologies will include deformation monitoring through the installation of fiberoptic cables and other appropriate technologies.